(ADV7282AM)CVBS-diff lock problem.

Hi!

Can somebody help about this?

It will be a great help if you help me.

Best regards

Kawa

Hi!

Thank you for your reply.

Since it is confirmed by register read back that the lock has already been removed, we will confirm with the customer whether to use the INT pin.
Also, it is confirmed that the output is NTSC - M, but I will check if it can be locked with AUTO DETECT.

How about using some Antialiasing Filters or other filter?

Best regards

kawa

Hi,

For lost lock :0x10 -0x07

The following example will describe how to set the interrupt pin to go from a
high state to a low state when the ADV7282 has lost lock to the inputted video.The interrupt will remain low until cleared.
1) Enter the Interrupt/VDP Sub Map by setting register 0x0E bit [5] to 1
2) Program the interrupt to drive low when active and to stay low until cleared: In register 0x40 write 0xD1
3) Unmask (i.e. activate) the unlock interrupt: set register 0x44 bit[1] to 1.
4) Clear the interrupt by writing 1 to register 0x43 bit [1]. (Note the bit will automatically reset to 0 after being written to).
5) Re-enter the User Map: set register 0x0E bit [5] to 0.
Note this should be run after a normal script has been run on the ADV7282.
Please refer https://ez.analog.com/docs/DOC-3108. Believe this would be more helpful for you.

Line length is nonstandard: 0x12 -0x10

  Try setting up the ADV7282 to auto detect the input standard and enable all standards to be detected.
If the camera is outputting a non-standard version of NTSC,then the ADV7282 may not be able to lock to it.
  Please refer https://ez.analog.com/thread/92777-adv7188-line-length-recognition.

Thanks,

Poornima

Hi,

 The ADV7282 have anti aliasing filters that are basically low pass filters designed to remove high frequency noise (outside analog video bandwidth) on the Ain lines.These filters have a -2 dB cut off of 10 MHz.
 For anti aliasing ,luma and chroma filter details,Please refer page 11,22,25 in adv7282a user guide

The ADV7180/ADV7182/ADV728x video decoders are designed to be low cost analog to digital video decoders and as such they only have 2D comb YC separation filters.2D comb filters are good at separating the luma and chroma information.

  3D comb will result in fewer artifacts output to the screen. However  a number of frames of video need to be stored in an external SDRAM chip in order for the 3D comb filter to work. This will add a delay from inputted video to outputted video.

Thanks,

Poornima

Hi !

Thank you for your reply.

I know what AA filter is.

But there is no detail about filter.

Can you tell each specification about these filters?

Also I am not asking about each filter.

Do you have any idea what cause this un-lock problem?

Best regards

Kawa

Hi,
   An anti aliasing filter is required on all four data channels (R, G, B, and CVBS). The order of this filter is reduced as all of the signals are sampled at 54 MHz.
   Four internal anti-alias filters to remove out-of-band noise on standard definition input video signals.Please refer AV7181c manual
   Note : The ADV7180 or any decoder,does have 10MHz anti-aliasing filters (AAF) that remove EMI above the CVBS video frequency band.

   Please refer https://ez.analog.com/message/130191?commentID=130191#comment-130191

Do you have any idea what cause this un-lock problem?
 The interrupt pin to toggle when a lock event occurs. configure according to the below script.
Enable Analog Video Lock/Unlock Interrupts:

42 0E 20 ; Enter Interrupt Map
42 44 03 ; Unmask SD_LOCK and SD_UNLOCK interrupts
42 43 03 ; Clear Clear SD_LOCK and SD_UNLOCK interrupts
42 40 D1 ; Set INTRQ pin to drive low when active and remain low until cleared
42 0E 00 ; Enter User Map
End

Clear Analog Video Lock/Unlock Interrupts:
42 0E 20 ; Enter Interrupt Map
42 43 03 ; Clear Clear SD_LOCK and SD_UNLOCK interrupts
42 0E 00 ; Enter User Map
End
Please refer https://ez.analog.com/message/202565?commentID=202565#comment-202565

Thanks,

Poornima

Hi !

Thank you for your reply.

I understood.

best regards

Kawa